Method SetFieldBuilder

cpp/src/arrow/json/parser.cc:838–858

\brief helper for Key() functions sets the field builder with name key, or returns false if there is no field with that name

  /// sets the field builder with name key, or returns false if
  /// there is no field with that name
  bool SetFieldBuilder(std::string_view key, bool* duplicate_keys) {
    auto parent = Cast<Kind::kObject>(builder_stack_.back());
    field_index_ = parent->GetFieldIndex(key);
    if (ARROW_PREDICT_FALSE(field_index_ == -1)) {
      return false;
    }
    if (field_index_ < absent_fields_stack_.TopSize()) {
      *duplicate_keys = !absent_fields_stack_[field_index_];
    } else {
      // When field_index is beyond the range of absent_fields_stack_ we have a duplicated
      // field that wasn't declared in schema or previous records.
      *duplicate_keys = true;
    }
    if (*duplicate_keys) {
      status_ = ParseError("Column(", Path(), ") was specified twice in row ", num_rows_);
      return false;
    }
    builder_ = parent->field_builder(field_index_);
    absent_fields_stack_[field_index_] = false;
    return true;
  }

  Status EndObjectImpl() {
    auto parent = builder_stack_.back();